Intro: Blade Honing Kit
The following instructable shows how to make a blade honing kit. Honing is necessary to get razor-sharp edges on knives or tools. By following the next steps, you'll be able to make the compound as well as the strops.
Step 1: Grate
In this step, you will need to find some polishing compound blocks. These can be purchased at most home improvement stores. They are typically used with buffing wheels to give metals a mirror finish. Use a cheese grater to get fine shavings off the compound blocks. Work your way up from the finest (5) to the roughest (1) otherwise you will contaminate the finer compounds.
Step 2: Mix
In this step, mix each of the grated compounds with a bit of petroleum jelly. Usually petroleum jelly can be found in the pharmacy section of most stores. Exact precision does not matter, but a ratio of jelly to compound of 1:1 to 2:3 should suffice.
Step 3: Melt
In this step, you will need to melt the mixtures of petroleum jelly and grated compound. When the temperature is just high enough, the jelly and compound will both be liquid and mix. If the mixture starts smoking, the temperature is too high. When the mixture is liquid, you should let it cool so that it hardens but remains as a paste. If it gets too hard, more petroleum jelly is needed. When it has cooled down enough, it should be mixed so that it is uniform and stored in containers. Make sure to mark the containers appropriately.
Step 4: Strops
Find an old, wide, leather belt and sand both sides. Cut the belt into five segments and cut 1/4" thick wood segments of the same width and length as the belt segments.
Step 5: Oil Proof
In this step, you will need to oil-proof the top-face of the wooden pieces for application of boiled linseed oil and paste wax in the next step. Dextrin is a simple oil-proof compound that is water soluble. It is made by taking a starch and thermally decomposing it into dextrin. Normally, starch is not very soluble in room-temperature water, whereas dextrin is very soluble. To make the dextrin take corn starch (takes a long time to convert) or tapioca starch (takes a shorter time to convert) and heat it to 450 °F for 30 minutes to 2 hours. To shorten the conversion time, use a cookie sheet and make the starch layer very thin so that it heats quickly and evenly. Dissolve the dextrin in water until it becomes a watery syrup. Paint 3-4 layers of this syrup onto the top-face of wooden pieces. Specifically, the top-face is the area to which the leather belt segment will adhere. Let it dry before going to the next step.
Step 6: Finish
Apply a layer of boiled linseed oil to each wood segment and heat the segments to 300 °F inside an oven. This will cause the boiled linseed oil to partially cure. While still hot, remove the segments, wipe them, and repeat 2-3 more times. After the last time, let the wood cool. Apply paste wax so that the wood is no longer sticky. Dissolve the dextrin layer to expose the top-face by placing the wood in water. Use a scour pad to quicken the process. When done, wipe and let the wood dry over a few hours.
SAFETY: Do not throw away any towels or rags with boiled linseed oil. Doing so is a known fire hazard and could spontaneously catch fire, especially in elevated temperatures. Instead, soak them in water and throw them away in a sealed container with water.
Step 7: Mark
In this step, mark the wood segments 1 to 5 with brass screws. Create two templates to to assist you.
Step 8: Join
In this step, join the wood and belt segments together. First, sand the top-face of the wood. Apply contact cement to the sanded top-face and to the rougher face of the belt segments. Wait 10 minutes for the glue to dry before sticking the two pieces together, contact cement is unusual in that it needs to dry before it is joined. Use a rolling pin for firm adhesion between the belt and wood.
Step 9: Load & Use
You can now use the strops with the compound. To do so, load a thin layer of compound onto each strop. If there is too much friction while honing, you may need to reload the strop with more compound. Read GaroP's instructable for an introduction to stropping. Remember to start with the coarse compound (1) and step through to the fine compound (5). In between, remember to wipe the knife or tool edge so that you do not contaminate the finer strops with coarse compound.
Another way to use the compound is with a flat surface such as a granite tile or piece of glass. Apply compound to a strip of kraft paper (lunch bag paper) and use it as a strop. You can tape the edges of the kraft paper to the flat surface to make the stropping process easier.